The invention relates to the reading of a piece of information coded in accordance with a code of strokes.
It is known that these codes are constituted by a succession of reflecting strokes, for example black and white, of different widths and that the reading of this information from the support is carried out by optical-electronic detection of a luminous ray reflected by the support. The code defines a certain number of utility characters and security characters corresponding to the images of the support.
In certain applications, for example the reading "on the run" of an identification pass carried by the user which traverses a control area, or by a package transported on a conveyor belt, the presentation of the card in movement is such that, in the course of successive sweeps carried out by the reading device, the luminous beam, when it has a constant direction, traverses the card in a position which is inclined with respect to the strokes, so that only a part of the strokes is traversed at each sweep.
A known solution for alleviating this inconvenience consists in carrying out a sweep of variable inclination. This process leads to a correct reading, but is very onerous because it requires the employment of a complex optical-mechanical sweeping device, of difficult manufacture.